Proficiently in vendor-specific configuration syntax & operation - Juniper
Strong intimacy with IPv4 network management, with at least 5 years of relevant experience
Extensive knowledge of OSPF, BGP and other commonly used routing protocols
Deployment knowledge of high connection rate load balancing and designing highly available services
Advanced NMS configuration and tuning experience; acceptable tools include: Nagios, rrdtool
Strong knowledge of at least one administrative scripting languages, such as: Bash, Perl, PHP or Ruby
Familiar with DNS, HTTP, SMTP, RADIUS, LDAP protocols - can "speak" these protocols
Ability to recognize the right tool for the right situation/problem
The ability to take initiative, solve problems, and communicate effectively in a strong team focused environment
Excellent communication skills, capable of explaining highly technical problems in "plain" English
Strong document ethic capable of maintaining and authoring diagrams, procedures & policies - not afraid to use aggressive script commenting or wiki
Ability to lift 50+ lbs computer equipment and hardware as needed
Tools We Like:

Experience with sFlow or NetFlow-based analysis tools
Configuration and operational experience with security appliances, such as firewalls and DoS mitigation hardware
Strong negotiation skills with ISP transit, CDN and other network providers
Participate in frequent security audits, vulnerability scans & mitigation
Experienced operator of application delivery controllers or load balancers for continuous application availability
Comfortable working in a very dynamic start-up environment
A college degree and/or technical certificate is helpful, but actual industry experience and knowledge is key
Active user of Tumblr
Contributing back to the FOSS (Free or Open Source Source) community, as both programs and knowledge sharing (ie: blog posts)
Founded by David Karp in New York City in 2007, Tumblr is a microblogging platform that allows users to effortlessly share anything. Tumblr now hosts over 70 million blogs with over 34 billion posts to date. Our pageview to engineer ratio is 0.5 billion PV per month to 1 engineer. This means every line of code every developer writes has a huge impact. We are focused on building tools and technologies that will advance the state of the art in dealing with massively scaled websites as we quickly grow past 50,000 requests and 1,400 posts per second. We are also excited to deliver a range of new products that will enable users to share their own creative content, discover content, and connect to one another in new ways.